Analysis of the current status of bone density among primary and secondary school students and its influencing factors

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RESULTS This study found that BMD among school-age children increased with age. Boys had generally higher BMD than girls. Among children with normal body type, BMI was positively associated with BMD, whereas among overweight and obese children, BMI was negatively associated with BMD. Multivariate regression analysis showed that consuming at least one egg per day (β = 0.011, 95% CI: 0.003–0.019) and at least two servings of fruit per day (β = 0.009, 95% CI: 0.001–0.017) were independent protective factors for BMD. Notably, high intake of dairy products did not show significant benefits in the overweight/obese group (p > 0.05), suggesting that body type may attenuate the beneficial effects of dietary calcium. Pediatrics Introduction 1.1.1 Source of Information This data was obtained from the ‘Assessment of Milk Consumption and Health of Primary School Students’, a collaborative project of the China Association for Student Nutrition & Health Promotion (CASN&HP). 1.1.2 Study Participants A total of 708 school-aged children in grades 3 to 5 were selected as study participants from four primary schools in Yichang City, Hubei Province, between July 2021 and December 2021. Among them, 358 were male (50.56%) and 350 were female (49.44%). Inclusion criteria: Students in grades 3, 4, and 5 of the randomly selected primary schools who agreed to participate in this survey with informed consent provided either by themselves or their parents. Exclusion criteria: Students with lactose intolerance or dairy allergies; or those diagnosed within one year prior to the survey with any of the following conditions: liver disease, kidney disease, skeletal system disease, diabetes, hyperthyroidism or hypothyroidism, or other endocrine disorders. 1.1.3 Estimation of Sample Size The sampling design of the project takes into account both the principle of cost-effectiveness and the feasibility of the sampling scheme, and also considers the balance of sample distribution and the differences between urban and rural areas. A random sampling method was adopted. Considering a correlation coefficient of 0.2 between diet and bone mineral density, the sample size was calculated using PASS software through Spearman correlation test simulation analysis, yielding a required sample size of 321 cases. Taking into account a 20% loss to follow-up rate, the minimum sample size was increased to 401 cases. In this study, a total of 728 questionnaires were distributed. After excluding cases lost to follow-up and incomplete questionnaires, 708 valid questionnaires were collected. 1.2 Research Methods 1.2.1 Questionnaire Survey A self-designed questionnaire was used to collect information from all students, and the investigators received training. The questionnaire included: (1) Student Basic Information Form: including school name, school location, student name, gender, date of birth, grade, student ID number, and ID card number. This form was completed by the investigator, who also recorded the survey time. After the survey point project team reviewed all questionnaires and corrected any errors or omissions by re-interviewing students, parents, or teachers, both the investigator and reviewer signed the forms. (2) Student Learning and Health Status Questionnaire: included lifestyle habits, sleep schedules, and mental health. (3) Student Health Behavior Questionnaire: included dietary behavior, physical activity, screen time, and sleep. 1.2.2 Dietary Survey The food frequency questionnaire (FFQ) is a method for estimating the frequency and quantity of specific food intake by respondents over a certain period. Using this method, investigators can collect dietary data ranging from a few days to one year, allowing quick access to participants' daily intake and long-term dietary patterns, and potential correlations with diseases. This study mainly collected data on dietary intake types, frequency, and quantity. The food categories included 13 types such as cereals, tubers, vegetables, fruits, soy products, and nuts. Food frequency was categorized as never, daily, weekly, or monthly. Researchers provided standard portion size photographs, and under teachers' guidance, participants estimated their typical intake. Average daily intake was calculated using the frequency and portion size of each food item. 1.2.3 Medical Examination: Bone Density Test Bone mineral density (BMD) was measured using the Korean OsteoSys brand, model EXA-3000, employing dual-energy X-ray absorptiometry (DXA). As children are in a growth phase and bone disorders often affect cortical bone, the recommended measurement sites are the proximal one-third of the forearm or the whole body. BMD is typically assessed using Z-scores: Z-score = (measured BMD – mean BMD of same-race, same-sex, same-age population) / standard deviation of same population. In general, normal Z-scores for children range from − 1 to 2. A Z-score below − 1.0 suggests low bone mineral density. 1.2.4 Evaluation Criteria for Thinness, Overweight, and Obesity The evaluation criteria for thinness, overweight, and obesity refer to the "Comprehensive Evaluation of Children and Adolescents Development" (GBT 31178 − 2014) and "Screening for Overweight and Obesity among School-Age Children and Adolescents" (WS/T 586–2018). Body mass index (BMI) is calculated as weight (kg) / height² (m). Children whose BMI is lower than the age- and sex-specific reference value are classified as thin. Children whose BMI is equal to or greater than the overweight cutoff but less than the obesity cutoff are considered overweight. Children whose BMI is equal to or greater than the obesity cutoff are considered obese. The overweight BMI values for males aged 8, 9, 10, and 11 are 18.1, 18.9, 19.6, and 20.3 kg/m², respectively; for females, 18.1, 19.0, 20.0, and 21.1 kg/m², respectively. The obesity BMI values for males aged 8, 9, 10, and 11 are 20.3, 21.4, 22.5, and 23.6 kg/m², respectively; for females, 19.9, 21.0, 22.1, and 23.3 kg/m², respectively. Children are classified as thin when BMI values are below 13.8, 14.0, 14.3, and 14.7 kg/m² for males aged 8, 9, 10, and 11, and below 13.4, 13.7, 14.1, and 14.6 kg/m² for females of the same ages. 1.3 Statistical Methods Epidata 3.1 was used to construct the data entry database for the questionnaire and physical examination forms. Data entry was performed independently by two individuals, and all questionnaires were reviewed to eliminate invalid responses. Statistical analysis was conducted using SPSS version 27.0. Continuous variables were described using mean ± standard deviation. Differences in bone mineral density for independent continuous variables were analyzed using the t-test. For comparisons among more than two groups, one-way analysis of variance (ANOVA) was used. The significance level was set at α = 0.05. Multivariate linear regression analysis was used to assess the influence of multiple factors. Logistic multivariate linear regression was applied to evaluate the association between different dietary patterns and bone mineral density. A P-value of < 0.05 was considered statistically significant. RESEARCH METHODS Childhood and adolescence are critical windows for skeletal development, during which approximately 90% of bone mass is accumulated [7]. Bone mineral density (BMD), as a core indicator of skeletal health, directly affects the risk of developing osteoporosis in adulthood. In recent years, changes in dietary patterns among primary and secondary school students (e.g., increased intake of sugary beverages and processed foods), as well as the prevalence of sedentary lifestyles, may pose potential threats to bone development. Existing domestic studies have mostly focused on children in northern or economically developed regions, with a lack of systematic analyses regarding BMD characteristics and influencing factors in central areas, especially in small and medium-sized cities. This study aims to fill this regional gap through multidimensional data (dietary intake, behavioral factors, and anthropometrics), and to provide empirical evidence for formulating regional nutrition intervention strategies. Based on the “Milk Consumption and Health Assessment among Primary School Students” project, this study focuses on school-age children in Yichang City, aiming to reveal the current status of BMD and its association with dietary intake and body type, thus providing a basis for early intervention. Questionnaire survey: All students completed a self-designed questionnaire. The food frequency questionnaire (FFQ) was validated through a pilot study for reliability and validity (Cronbach's α = 0.82) and included 13 categories of food. Investigators used standardized food models (e.g., a 50 g cereal bowl and a 100 mL milk cup) to assist children in estimating the amount of a single intake. The frequency of each food group was converted to an average daily intake (g/day), and nutrient intake (e.g., calcium, vitamin D) was calculated based on the Dietary Guidelines for Chinese Residents (2022 edition) . The questionnaire consisted of: (1) Basic information form for students (2) Survey on students’ academic performance and health status (3) Survey on students’ health-related behaviors Dietary survey: The food frequency questionnaire (FFQ) is a method used to estimate the frequency and amount of consumption of specific foods by respondents over a defined period. Medical examination - Bone density testing: Before testing, operators received standardized training, and the equipment was calibrated daily using manufacturer-provided standard phantoms. The measurement site was the distal one-third of the radius of the non-dominant forearm. Each child was measured twice, and the average was taken. If the difference exceeded 5%, a third measurement was conducted. Z-scores were calculated according to the Chinese Children’s Bone Mineral Density Reference Standards (2017 edition) . A Z-score ≤ − 2.0 was defined as “low bone mineral density,” and − 2.0 < Z ≤ − 1.0 was defined as “bone mass insufficiency.” Bone mineral density measurement: Performed using the Korean brand QsteoSvs, model EXA-3000, via dual-energy X-ray absorptiometry (DEXA). Criteria for evaluating thinness, overweight, and obesity: The evaluation criteria referred to the Comprehensive Evaluation of Development Levels of Children and Adolescents (GBT 31173 − 2014) and Screening for Overweight and Obesity in School-Age Children and Adolescents (WS/T 586–2018) . Body mass index (BMI) was calculated as weight (kg) divided by the square of height (m²). When the BMI was below the age- and sex-specific cutoff, the child was classified as thin. When the BMI was greater than or equal to the age- and sex-specific overweight threshold but below the obesity threshold, the child was classified as overweight. When the BMI was greater than or equal to the obesity threshold for the corresponding age and sex, the child was classified as obese. Statistical analysis: EpiData 3.1 was used to establish the database for the questionnaire and physical examination data, with double entry to ensure accuracy. Invalid questionnaires were excluded after screening. Statistical analysis was performed using SPSS 22.0. In addition to univariate analyses, stratified regression models were used to control for confounding variables: Model 1 : Adjusted for demographic variables (sex, age, and urban/rural residence) Model 2 : Added BMI group based on Model 1 Model 3 : Further included significant dietary factors (e.g., frequency of egg and fruit consumption) Multicollinearity was assessed (variance inflation factor, VIF < 5), and residual analysis was conducted to ensure model robustness. Results 2.1 Basic Characteristics of the Study Subjects : See Table 1 for results. Table 1 Bone Density Levels in School-Age Children with Different Characteristics(x̅±s) Basic Characteristics Clusters Number of cases(%) BMD(g/cm2) P- value Gender <0.001 Male 358(50.6) 0.264 ± 0.045 Female 350(49.4) 0.253 ± 0.048 Nationality 0.386 Han nationality 628(88.7) 0.262 ± 0.041 Minority 80(11.3) 0.254 ± 0.038 Area 0.139 Village 343(48.4) 0.251 ± 0.047 City 365(51.6) 0.266 ± 0.042 Annual household income 0.041 < 60000¥ 276(39.0) 0.242 ± 0.047 ≥ 60000¥ 372(61.0) 0.268 ± 0.033 Age of the students 0.044 10y 225(31.8) 0.245 ± 0.041 11y 227(32.1) 0.249 ± 0.043 12y 256(36.1) 0.257 ± 0.042 Grade 0.016 4th grade 235(33.2) 0.245 ± 0.041 5th grade 238(33.6) 0.248 ± 0.039 6th grade 235(33.2) 0.257 ± 0.046 Body shape <0.001 regular 520(73.4) 0.248 ± 0.052 overweight 73(10.3) 0.263 ± 0.046 obese 36(5.1) 0.264 ± 0.037 emaciated 79(11.2) 0.228 ± 0.042 The results in Table 1 show that bone mineral density (BMD) at various anatomical sites was positively correlated with age, indicating that BMD increased with advancing age. In addition, a positive correlation was observed between BMI and BMD in children with normal body type, while a negative correlation was found in overweight and obese children. Table 2 Analysis of Differences in Bone Mineral Density by Age, Gender, and Bone Mineral Density Scores Age Gender BMD (g /cm2) Z-value number of cases(%) T-value P-value 10y 4.321 <0.001 male(n = 111) 0.257 ± 0.042 ≤ 1.0 15(13.5) female(n = 114) 0.240 ± 0.039 20(17.5) 11y 4.498 <0.001 male(n = 115) 0.258 ± 0.037 ≤-1.0 21(18.2) female(n = 112) 0.243 ± 0.039 17(15.2) 12y 2.615 <0.001 male(n = 132) 0.275 ± 0.044 ≤-1.0 14(10.6) female(n = 124) 0.272 ± 0.048 12(9.7) Table 3 Bone Densitometry and Dietary and Lifestyle Survey Results for Students in Grades 4–6(x̅±s) Activities Clusters Number of cases(%) BMD(g /cm2) F-value P -value Cereals (times/d) 1.361 0.257 ≥ 3 434(67.4) 0.255 ± 0.041 1–2 153(23.8) 0.261 ± 0.044 <1 57(8.8) 0.253 ± 0.040 Potatoes (times/d) ≥ 3 308(48.2) 0.257 ± 0.041 3.284 0.038 1–2 187(29.2) 0.260 ± 0.044 <1 144(22.6) 0.249 ± 0.041 Legumes (times/d) ≥ 3 200(31.1) 0.260 ± 0.040 2.232 0.108 1–2 199(30.9) 0.260 ± 0.043 <1 244(38.0) 0.252 ± 0.042 Meat (times/d) ≥ 3 129(20.1) 0.263 ± 0.042 2.427 0.089 1–2 405(63.1) 0.255 ± 0.042 <1 108(16.8) 0.252 ± 0.039 Eggs(times/d) ≥ 3 370(57.9) 0.258 ± 0.041 0.047 1–2 148(23.2) 0.260 ± 0.046 <1 121(18.9) 0.248 ± 0.039 Vagetables(times/d) ≥ 3 196(30.8) 0.260 ± 0.042 1.445 0.237 1–2 358(56.2) 0.254 ± 0.039 <1 83(15.0) 0.254 ± 0.050 Fruits(times/d) ≥ 3 99(15.5) 0.262 ± 0.042 3.279 0.038 1–2 392(61.3) 0.257 ± 0.041 <1 148(23.2) 0.249 ± 0.043 Fish and shrimp (times/d) ≥ 3 78(12.2) 0.253 ± 0.046 0.376 0.687 1–2 169(26.4) 0.258 ± 0.041 <1 393(61.4) 0.255 ± 0.041 Snacks(times/d) ≥ 3 125(19.5) 0.254 ± 0.042 1.587 0.205 1–2 179(27.9) 0.252 ± 0.043 <1 338(52.6) 0.259 ± 0.405 Fluid milk(times/d) ≥ 3 97(15.1) 0.263 ± 0.039 1.729 0.178 1–2 411(64.1) 0.255 ± 0.042 <1 133(20.8) 0.254 ± 0.042 Yogurt(times/d) ≥ 3 298(46.8) 0.260 ± 0.042 2.896 0.056 1–2 130(20.4) 0.256 ± 0.043 <1 209(32.8) 0.251 ± 0.038 Dairy beverages(times/d) ≥ 3 68(10.6) 0.256 ± 0.046 0.511 1–2 88(13.8) 0.252 ± 0.034 <1 484(75.6) 0.257 ± 0.043 Table 4 Multiple Linear Regression/Logistic Regression of Basic Student Profile, Behavior and Bone Mineral Density Influencing factors Number of students(%) β 95% CI P-value Gender 708 -0.10 (-0.029, -0.016) <0.001 Age 708 0.006 (0.001, 0.006) 0.01 Grade 708 0.007 (0.002, 0.007) 0.005 BMI 499 0.003 ( 0.002 , 0.005 ) < 0.001 Area 499 0.003 (-0.002, 0.012) 0.138 Number of breakfasts 499 0.007 (-0.004,0.006) 0.901 Frequency of Cereal Intake 499 0.006 (-0.004,0.007) 0.220 Frequency of Potato Intake 499 0.003 (-0.005,0.010) 0.276 Frequency of Legume Intake 499 0.001 (-0.007,0.006) 0.219 Frequency of Meat Intake 499 -0.003 (-0.001,0.008) 0.858 Frequency of Egg Intake 499 0.003 (0.001,0.007) 0.018 Frequency of Vegetable Intake 499 -0.002 (-0.002,0.004) 0.294 Frequency of Fruit Intake 499 0.005 (-0.001,0.007) 0.468 Frequency of Nut Intake 499 0.001 (0.001,0.009) 0.017 Frequency of Fish and Shrimp Intake 499 0.003 (-0.001,0.013) 0.223 Frequency of Snack Intake 499 -0.005 (-0.003,0.009) 0.298 Frequency of Milk Intake 499 0.005 (-0.002,0.010) 0.203 Frequency of Yogurt Intake 499 0.001 (-0.003,0.007) 0.531 Frequency of Milk Powder Intake 499 -0.001 (-0.008,0.005) 0.925 Sleeping Time 499 0.002 (-0.001,0.003) 0.091 The final number of students with complete inclusion of each food intake frequency was 499, after the elimination of incomplete dietary frequencies in the dataset. The demographic characteristics of the students included gender, age, grade, BMI, and region. The dietary intake frequency of the students included the frequency of consumption of cereals, potatoes, legumes, meat, eggs, vegetables, fruits, fish and shrimp, snacks, liquid milk, yogurt, and dairy-containing beverages. The correlation between these variables and bone density was subsequently calculated. The results demonstrated that, in the base case, boys exhibited higher bone mineral density (BMD) compared to girls. Age, grade, and BMI demonstrated a positive correlation with BMD. Additionally, dietary intake of cereals, potatoes, eggs, and fruits exhibited a positive correlation with BMD. Discussion This study found that bone mineral density (BMD) in school-aged children increases with age. Boys generally exhibited higher BMD levels than girls. Among children with normal body composition, body mass index (BMI) was positively correlated with BMD, while among overweight and obese children, BMI was negatively correlated with BMD. Increased dietary intake of cereals, tubers, eggs, and fruits was associated with a reduced risk of low BMD. These associations warrant further investigation through experimental studies. The BMD of school-aged children in Yichang City is jointly influenced by age, sex, body composition, and dietary patterns. Maintaining a healthy body weight serves as the foundation for bone health. On this basis, increasing the intake of eggs and fruits can further improve BMD. The negative effects of overweight and obesity on bone metabolism deserve heightened attention. Childhood and adolescence are periods of rapid bone mass accrual. During this phase, bone mass in females increases from approximately 70 g to 2400 g, and in males from approximately 95 g to 3300 g. This is a critical period for the accumulation of peak bone mass. Promoting bone mass accumulation starting from childhood and adolescence can significantly enhance peak bone mass, delay the onset of osteoporosis, and mitigate its severity. Since BMD serves as a comprehensive indicator of bone mass status, research on BMD in children and adolescents holds significant public health relevance. Skeletal growth is closely related to physical growth and development. As age increases, height and weight of children and adolescents increase accordingly, along with skeletal growth and an increase in BMD. Numerous studies have demonstrated that BMD increases with age during childhood and adolescence 【 4 , 5 , 6 】 .Consistent with these findings, the present study also observed a clear positive correlation between BMD at various skeletal sites and age, indicating that BMD increases with age. Limitations This study has several limitations. First, it was conducted at a single school, which may limit generalizability. Second, the retrospective design relied on questionnaire results, and incomplete questionnaire led to the exclusion of some cases. Third, dietary data were self-reported by children, which may introduce bias. Despite these limitations, the study provides valuable insights into the correlation between dietary intake and bone density. Conclusions Bone mineral density (BMD) in school-aged children increases with age. Boys generally exhibited higher BMD levels than girls. Among children with normal body composition, body mass index (BMI) was positively correlated with BMD, while among overweight and obese children, BMI was negatively correlated with BMD. Increased dietary intake of cereals, tubers, eggs, and fruits was associated with a reduced risk of low BMD. These associations warrant further investigation through experimental studies. The BMD of school-aged children in Yichang City is jointly influenced by age, sex, body composition, and dietary patterns. Maintaining a healthy body weight serves as the foundation for bone health. On this basis, increasing the intake of eggs and fruits can further improve BMD. The negative effects of overweight and obesity on bone metabolism deserve heightened attention. Declarations Ethics Statement This manuscript presents a conceptual and methodological protocol developed within an independent research program. No data involving human participants were collected, generated, or analyzed as part of the present work. The proposed protocol is intended to inform future empirical research involving vulnerable pediatric populations. Formal ethical approval will be sought from the appropriate Human Research Ethics Committee (HREC) at the host institution prior to the commencement of any study involving human participants. The protocol has been designed in accordance with the precautionary principle. Given the limited capacity for verbal assent in the target population, the absence of a behavioral response is not interpreted as consent. The protocol explicitly integrates physiological and behavioral indicators as markers of potential non-verbal dissent, and any such indicators would lead to immediate termination of the session in future implementations. Generative AI tools were used during the preparation of the manuscript to facilitate linguistic revision from French to academic English. This tool was not used to generate scientific content, interpret data, or draw conclusions. All content has been reviewed, verified, and approved by the author. Ethics Statement This retrospective analysis of clinical data qualified for an exemption from ethical approval by the Ethics Committee of Tongji Hospital affiliated to Tongji Medical College of HUST. The study adhered to the ethical principles of the Declaration of Helsinki. The publication of this report and any accompanying images has been granted a waiver of written informed consent from the patient. References Chinese Nutrition Society (2001) Chinese Dietary Reference Intakes [M]. China Light Industry, Beijing, pp 17–19 Ge KY, Chang SY (1999) Dietary intake of micronutrients by Chinese residents. Acta Nutrimenta Sinica 21(1):1–7 Wang Y (2012) A study on the relationship between maternal dietary quality, gestational weight gain, and neonatal birth weight (Master's thesis). Anhui Medical University, Anhui, China General Administration of Quality Supervision (2014) Inspection and Quarantine of the People's Republic of China, & Standardization Administration of the People's Republic of China. *Comprehensive evaluation of developmental level for children and adolescents*. GB/T 31178 – 2014. [Chinese national standard]. Xiong F, Yang F, Yang SF et al (2014) Relationship between 25-hydroxyvitamin D and bone mineral density in children aged 0–7 years. *Chinese J Contemp Pediatr 16(9):883–886 Wang YN (2018) Methodological comparison of growth curve construction and its medical application studies (Master's thesis). Chongqing Medical University, Chongqing, China Nakavachara P, Pooliam J, Weerakulwattana L et al A normal reference of bone mineral density (BMD) measured by dual energy X-ray absorptiometry in healthy thai childrenand adolescents aged 5–18 years: a new reference for Southeast Asian Populations[J]. Plos One,2014,9(5):e97218 Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Among them, 358 were male (50.56%) and 350 were female (49.44%).\u003c/p\u003e \u003cp\u003eInclusion criteria: Students in grades 3, 4, and 5 of the randomly selected primary schools who agreed to participate in this survey with informed consent provided either by themselves or their parents.\u003c/p\u003e \u003cp\u003eExclusion criteria: Students with lactose intolerance or dairy allergies; or those diagnosed within one year prior to the survey with any of the following conditions: liver disease, kidney disease, skeletal system disease, diabetes, hyperthyroidism or hypothyroidism, or other endocrine disorders.\u003c/p\u003e \u003cp\u003e \u003cb\u003e1.1.3 Estimation of Sample Size\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe sampling design of the project takes into account both the principle of cost-effectiveness and the feasibility of the sampling scheme, and also considers the balance of sample distribution and the differences between urban and rural areas. A random sampling method was adopted. Considering a correlation coefficient of 0.2 between diet and bone mineral density, the sample size was calculated using PASS software through Spearman correlation test simulation analysis, yielding a required sample size of 321 cases. Taking into account a 20% loss to follow-up rate, the minimum sample size was increased to 401 cases. In this study, a total of 728 questionnaires were distributed. After excluding cases lost to follow-up and incomplete questionnaires, 708 valid questionnaires were collected.\u003c/p\u003e \u003cp\u003e \u003cb\u003e1.2 Research Methods\u003c/b\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003e1.2.1 Questionnaire Survey\u003c/b\u003e \u003c/p\u003e\u003cp\u003eA self-designed questionnaire was used to collect information from all students, and the investigators received training. The questionnaire included:\u003c/p\u003e \u003cp\u003e(1) Student Basic Information Form: including school name, school location, student name, gender, date of birth, grade, student ID number, and ID card number. This form was completed by the investigator, who also recorded the survey time. After the survey point project team reviewed all questionnaires and corrected any errors or omissions by re-interviewing students, parents, or teachers, both the investigator and reviewer signed the forms.\u003c/p\u003e \u003cp\u003e(2) Student Learning and Health Status Questionnaire: included lifestyle habits, sleep schedules, and mental health.\u003c/p\u003e \u003cp\u003e(3) Student Health Behavior Questionnaire: included dietary behavior, physical activity, screen time, and sleep.\u003c/p\u003e \u003cp\u003e \u003cb\u003e1.2.2 Dietary Survey\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe food frequency questionnaire (FFQ) is a method for estimating the frequency and quantity of specific food intake by respondents over a certain period. Using this method, investigators can collect dietary data ranging from a few days to one year, allowing quick access to participants' daily intake and long-term dietary patterns, and potential correlations with diseases. This study mainly collected data on dietary intake types, frequency, and quantity. The food categories included 13 types such as cereals, tubers, vegetables, fruits, soy products, and nuts. Food frequency was categorized as never, daily, weekly, or monthly. Researchers provided standard portion size photographs, and under teachers' guidance, participants estimated their typical intake. Average daily intake was calculated using the frequency and portion size of each food item.\u003c/p\u003e \u003cp\u003e \u003cb\u003e1.2.3 Medical Examination: Bone Density Test\u003c/b\u003e \u003c/p\u003e \u003cp\u003eBone mineral density (BMD) was measured using the Korean OsteoSys brand, model EXA-3000, employing dual-energy X-ray absorptiometry (DXA). As children are in a growth phase and bone disorders often affect cortical bone, the recommended measurement sites are the proximal one-third of the forearm or the whole body. BMD is typically assessed using Z-scores:\u003c/p\u003e \u003cp\u003eZ-score = (measured BMD – mean BMD of same-race, same-sex, same-age population) / standard deviation of same population.\u003c/p\u003e \u003cp\u003eIn general, normal Z-scores for children range from − 1 to 2. A Z-score below − 1.0 suggests low bone mineral density.\u003c/p\u003e \u003cp\u003e \u003cb\u003e1.2.4 Evaluation Criteria for Thinness, Overweight, and Obesity\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThe evaluation criteria for thinness, overweight, and obesity refer to the \"Comprehensive Evaluation of Children and Adolescents Development\" (GBT 31178 − 2014) and \"Screening for Overweight and Obesity among School-Age Children and Adolescents\" (WS/T 586–2018). Body mass index (BMI) is calculated as weight (kg) / height² (m).\u003c/p\u003e \u003cp\u003eChildren whose BMI is lower than the age- and sex-specific reference value are classified as thin. Children whose BMI is equal to or greater than the overweight cutoff but less than the obesity cutoff are considered overweight. Children whose BMI is equal to or greater than the obesity cutoff are considered obese. The overweight BMI values for males aged 8, 9, 10, and 11 are 18.1, 18.9, 19.6, and 20.3 kg/m², respectively; for females, 18.1, 19.0, 20.0, and 21.1 kg/m², respectively. The obesity BMI values for males aged 8, 9, 10, and 11 are 20.3, 21.4, 22.5, and 23.6 kg/m², respectively; for females, 19.9, 21.0, 22.1, and 23.3 kg/m², respectively. Children are classified as thin when BMI values are below 13.8, 14.0, 14.3, and 14.7 kg/m² for males aged 8, 9, 10, and 11, and below 13.4, 13.7, 14.1, and 14.6 kg/m² for females of the same ages.\u003c/p\u003e \u003cp\u003e \u003cb\u003e1.3 Statistical Methods\u003c/b\u003e \u003c/p\u003e \u003cp\u003eEpidata 3.1 was used to construct the data entry database for the questionnaire and physical examination forms. Data entry was performed independently by two individuals, and all questionnaires were reviewed to eliminate invalid responses. Statistical analysis was conducted using SPSS version 27.0. Continuous variables were described using mean ± standard deviation. Differences in bone mineral density for independent continuous variables were analyzed using the t-test. For comparisons among more than two groups, one-way analysis of variance (ANOVA) was used. The significance level was set at α = 0.05. Multivariate linear regression analysis was used to assess the influence of multiple factors. Logistic multivariate linear regression was applied to evaluate the association between different dietary patterns and bone mineral density. A P-value of \u0026lt; 0.05 was considered statistically significant.\u003c/p\u003e "},{"header":"RESEARCH METHODS","content":"\u003cp\u003eChildhood and adolescence are critical windows for skeletal development, during which approximately 90% of bone mass is accumulated [7]. Bone mineral density (BMD), as a core indicator of skeletal health, directly affects the risk of developing osteoporosis in adulthood. In recent years, changes in dietary patterns among primary and secondary school students (e.g., increased intake of sugary beverages and processed foods), as well as the prevalence of sedentary lifestyles, may pose potential threats to bone development. Existing domestic studies have mostly focused on children in northern or economically developed regions, with a lack of systematic analyses regarding BMD characteristics and influencing factors in central areas, especially in small and medium-sized cities. This study aims to fill this regional gap through multidimensional data (dietary intake, behavioral factors, and anthropometrics), and to provide empirical evidence for formulating regional nutrition intervention strategies. Based on the “Milk Consumption and Health Assessment among Primary School Students” project, this study focuses on school-age children in Yichang City, aiming to reveal the current status of BMD and its association with dietary intake and body type, thus providing a basis for early intervention.\u003c/p\u003e\u003ch3\u003eQuestionnaire survey:\u003c/h3\u003e\u003cp\u003eAll students completed a self-designed questionnaire. The food frequency questionnaire (FFQ) was validated through a pilot study for reliability and validity (Cronbach's α = 0.82) and included 13 categories of food. Investigators used standardized food models (e.g., a 50 g cereal bowl and a 100 mL milk cup) to assist children in estimating the amount of a single intake. The frequency of each food group was converted to an average daily intake (g/day), and nutrient intake (e.g., calcium, vitamin D) was calculated based on the \u003cem\u003eDietary Guidelines for Chinese Residents (2022 edition)\u003c/em\u003e. The questionnaire consisted of:\u003c/p\u003e\u003cp\u003e(1) Basic information form for students\u003c/p\u003e\u003cp\u003e(2) Survey on students’ academic performance and health status\u003c/p\u003e\u003cp\u003e(3) Survey on students’ health-related behaviors\u003c/p\u003e\u003ch2\u003eDietary survey:\u003c/h2\u003e\u003cp\u003eThe food frequency questionnaire (FFQ) is a method used to estimate the frequency and amount of consumption of specific foods by respondents over a defined period.\u003c/p\u003e\u003ch3\u003eMedical examination - Bone density testing:\u003c/h3\u003e\u003cp\u003eBefore testing, operators received standardized training, and the equipment was calibrated daily using manufacturer-provided standard phantoms. The measurement site was the distal one-third of the radius of the non-dominant forearm. Each child was measured twice, and the average was taken. If the difference exceeded 5%, a third measurement was conducted. Z-scores were calculated according to the \u003cem\u003eChinese Children’s Bone Mineral Density Reference Standards (2017 edition)\u003c/em\u003e. A Z-score ≤ − 2.0 was defined as “low bone mineral density,” and − 2.0 \u0026lt; Z ≤ − 1.0 was defined as “bone mass insufficiency.”\u003c/p\u003e\u003ch3\u003eBone mineral density measurement:\u003c/h3\u003e\u003cp\u003ePerformed using the Korean brand QsteoSvs, model EXA-3000, via dual-energy X-ray absorptiometry (DEXA).\u003c/p\u003e\u003ch3\u003eCriteria for evaluating thinness, overweight, and obesity:\u003c/h3\u003e\u003cp\u003eThe evaluation criteria referred to the \u003cem\u003eComprehensive Evaluation of Development Levels of Children and Adolescents (GBT 31173 − 2014)\u003c/em\u003e and \u003cem\u003eScreening for Overweight and Obesity in School-Age Children and Adolescents (WS/T 586–2018)\u003c/em\u003e. Body mass index (BMI) was calculated as weight (kg) divided by the square of height (m²).\u003c/p\u003e\u003cul\u003e \u003cli\u003e \u003cp\u003eWhen the BMI was below the age- and sex-specific cutoff, the child was classified as thin.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eWhen the BMI was greater than or equal to the age- and sex-specific overweight threshold but below the obesity threshold, the child was classified as overweight.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eWhen the BMI was greater than or equal to the obesity threshold for the corresponding age and sex, the child was classified as obese.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e\u003ch2\u003eStatistical analysis:\u003c/h2\u003e\u003cp\u003eEpiData 3.1 was used to establish the database for the questionnaire and physical examination data, with double entry to ensure accuracy. Invalid questionnaires were excluded after screening. Statistical analysis was performed using SPSS 22.0. In addition to univariate analyses, stratified regression models were used to control for confounding variables:\u003c/p\u003e\u003cul\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eModel 1\u003c/b\u003e: Adjusted for demographic variables (sex, age, and urban/rural residence)\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eModel 2\u003c/b\u003e: Added BMI group based on Model 1\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003e \u003cb\u003eModel 3\u003c/b\u003e: Further included significant dietary factors (e.g., frequency of egg and fruit consumption)\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e\u003cp\u003eMulticollinearity was assessed (variance inflation factor, VIF \u0026lt; 5), and residual analysis was conducted to ensure model robustness.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e \u003cb\u003e2.1 Basic Characteristics of the Study Subjects\u003c/b\u003e:\u003c/p\u003e \u003cp\u003eSee Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e for results.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBone Density Levels in School-Age Children with Different Characteristics(x̅\u0026plusmn;s)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBasic Characteristics\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eClusters\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNumber of cases(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBMD(g/cm2)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP- value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e358(50.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.264\u0026thinsp;\u0026plusmn;\u0026thinsp;0.045\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e350(49.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.253\u0026thinsp;\u0026plusmn;\u0026thinsp;0.048\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNationality\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.386\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHan nationality\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e628(88.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.262\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMinority\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e80(11.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.254\u0026thinsp;\u0026plusmn;\u0026thinsp;0.038\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eArea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.139\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eVillage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e343(48.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.251\u0026thinsp;\u0026plusmn;\u0026thinsp;0.047\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e365(51.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.266\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnnual household income\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.041\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;60000\u0026yen;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e276(39.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.242\u0026thinsp;\u0026plusmn;\u0026thinsp;0.047\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;60000\u0026yen;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e372(61.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.268\u0026thinsp;\u0026plusmn;\u0026thinsp;0.033\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge of the students\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.044\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e225(31.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.245\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e11y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e227(32.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.249\u0026thinsp;\u0026plusmn;\u0026thinsp;0.043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e256(36.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.257\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.016\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4th grade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e235(33.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.245\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5th grade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e238(33.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.248\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6th grade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e235(33.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.257\u0026thinsp;\u0026plusmn;\u0026thinsp;0.046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBody shape\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eregular\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e520(73.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.248\u0026thinsp;\u0026plusmn;\u0026thinsp;0.052\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eoverweight\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e73(10.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.263\u0026thinsp;\u0026plusmn;\u0026thinsp;0.046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eobese\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e36(5.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.264\u0026thinsp;\u0026plusmn;\u0026thinsp;0.037\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eemaciated\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e79(11.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.228\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe results in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e show that bone mineral density (BMD) at various anatomical sites was positively correlated with age, indicating that BMD increased with advancing age. In addition, a positive correlation was observed between BMI and BMD in children with normal body type, while a negative correlation was found in overweight and obese children.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAnalysis of Differences in Bone Mineral Density by Age, Gender, and Bone Mineral Density Scores\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGender\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBMD (g /cm2)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eZ-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003enumber of cases(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eT-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e10y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e4.321\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u0026lt;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003emale(n\u0026thinsp;=\u0026thinsp;111)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.257\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026le;\u0026thinsp;1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e15(13.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003efemale(n\u0026thinsp;=\u0026thinsp;114)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.240\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e20(17.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e11y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e4.498\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u0026lt;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003emale(n\u0026thinsp;=\u0026thinsp;115)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.258\u0026thinsp;\u0026plusmn;\u0026thinsp;0.037\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026le;-1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e21(18.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003efemale(n\u0026thinsp;=\u0026thinsp;112)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.243\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e17(15.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e12y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e2.615\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u0026lt;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003emale(n\u0026thinsp;=\u0026thinsp;132)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.275\u0026thinsp;\u0026plusmn;\u0026thinsp;0.044\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u0026le;-1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e14(10.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003efemale(n\u0026thinsp;=\u0026thinsp;124)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e0.272\u0026thinsp;\u0026plusmn;\u0026thinsp;0.048\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e12(9.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBone Densitometry and Dietary and Lifestyle Survey Results for Students in Grades 4\u0026ndash;6(x̅\u0026plusmn;s)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eActivities\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eClusters\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNumber of cases(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eBMD(g\u0026nbsp;/cm2)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eF-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCereals (times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.361\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.257\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e434(67.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.255\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e153(23.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.261\u0026thinsp;\u0026plusmn;\u0026thinsp;0.044\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e57(8.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.253\u0026thinsp;\u0026plusmn;\u0026thinsp;0.040\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePotatoes (times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e308(48.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.257\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3.284\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.038\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e187(29.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.260\u0026thinsp;\u0026plusmn;\u0026thinsp;0.044\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e144(22.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.249\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLegumes (times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e200(31.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.260\u0026thinsp;\u0026plusmn;\u0026thinsp;0.040\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2.232\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.108\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e199(30.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.260\u0026thinsp;\u0026plusmn;\u0026thinsp;0.043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e244(38.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.252\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMeat (times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e129(20.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.263\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2.427\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.089\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e405(63.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.255\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e108(16.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.252\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEggs(times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e370(57.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.258\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.047\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e148(23.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.260\u0026thinsp;\u0026plusmn;\u0026thinsp;0.046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e121(18.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.248\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVagetables(times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e196(30.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.260\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.445\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.237\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e358(56.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.254\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e83(15.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.254\u0026thinsp;\u0026plusmn;\u0026thinsp;0.050\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFruits(times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e99(15.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.262\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3.279\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.038\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e392(61.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.257\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e148(23.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.249\u0026thinsp;\u0026plusmn;\u0026thinsp;0.043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFish and shrimp (times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e78(12.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.253\u0026thinsp;\u0026plusmn;\u0026thinsp;0.046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.376\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.687\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e169(26.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.258\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e393(61.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.255\u0026thinsp;\u0026plusmn;\u0026thinsp;0.041\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSnacks(times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e125(19.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.254\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.587\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.205\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e179(27.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.252\u0026thinsp;\u0026plusmn;\u0026thinsp;0.043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e338(52.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.259\u0026thinsp;\u0026plusmn;\u0026thinsp;0.405\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFluid milk(times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e97(15.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.263\u0026thinsp;\u0026plusmn;\u0026thinsp;0.039\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.729\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.178\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e411(64.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.255\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e133(20.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.254\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYogurt(times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e298(46.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.260\u0026thinsp;\u0026plusmn;\u0026thinsp;0.042\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e2.896\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.056\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e130(20.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.256\u0026thinsp;\u0026plusmn;\u0026thinsp;0.043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e209(32.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.251\u0026thinsp;\u0026plusmn;\u0026thinsp;0.038\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDairy beverages(times/d)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026ge;\u0026thinsp;3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e68(10.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.256\u0026thinsp;\u0026plusmn;\u0026thinsp;0.046\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.511\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u0026ndash;2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e88(13.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.252\u0026thinsp;\u0026plusmn;\u0026thinsp;0.034\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e484(75.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c4\"\u003e \u003cp\u003e0.257\u0026thinsp;\u0026plusmn;\u0026thinsp;0.043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMultiple Linear Regression/Logistic Regression of Basic Student Profile, Behavior and Bone Mineral Density\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInfluencing factors\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNumber of students(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eβ\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eP-value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGender\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e708\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.029, -0.016)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e708\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(0.001, 0.006)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e708\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.007\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(0.002, 0.007)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eBMI\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e499\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.003\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(\u003cb\u003e0.002\u003c/b\u003e, \u003cb\u003e0.005\u003c/b\u003e)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e\u0026lt;\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eArea\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.002, 0.012)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.138\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNumber of breakfasts\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.007\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.004,0.006)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.901\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Cereal Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.004,0.007)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.220\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Potato Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.005,0.010)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.276\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Legume Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.007,0.006)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.219\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Meat Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.001,0.008)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.858\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Egg Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(0.001,0.007)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.018\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Vegetable Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.002,0.004)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.294\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Fruit Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.001,0.007)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.468\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Nut Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(0.001,0.009)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.017\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Fish and Shrimp Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.001,0.013)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.223\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Snack Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.003,0.009)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.298\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Milk Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.002,0.010)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.203\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Yogurt Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.003,0.007)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.531\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFrequency of Milk Powder Intake\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e-0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.008,0.005)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.925\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSleeping Time\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e499\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e(-0.001,0.003)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e0.091\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe final number of students with complete inclusion of each food intake frequency was 499, after the elimination of incomplete dietary frequencies in the dataset. The demographic characteristics of the students included gender, age, grade, BMI, and region. The dietary intake frequency of the students included the frequency of consumption of cereals, potatoes, legumes, meat, eggs, vegetables, fruits, fish and shrimp, snacks, liquid milk, yogurt, and dairy-containing beverages. The correlation between these variables and bone density was subsequently calculated. The results demonstrated that, in the base case, boys exhibited higher bone mineral density (BMD) compared to girls. Age, grade, and BMI demonstrated a positive correlation with BMD. Additionally, dietary intake of cereals, potatoes, eggs, and fruits exhibited a positive correlation with BMD.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study found that bone mineral density (BMD) in school-aged children increases with age. Boys generally exhibited higher BMD levels than girls. Among children with normal body composition, body mass index (BMI) was positively correlated with BMD, while among overweight and obese children, BMI was negatively correlated with BMD. Increased dietary intake of cereals, tubers, eggs, and fruits was associated with a reduced risk of low BMD. These associations warrant further investigation through experimental studies. The BMD of school-aged children in Yichang City is jointly influenced by age, sex, body composition, and dietary patterns. Maintaining a healthy body weight serves as the foundation for bone health. On this basis, increasing the intake of eggs and fruits can further improve BMD. The negative effects of overweight and obesity on bone metabolism deserve heightened attention.\u003c/p\u003e \u003cp\u003eChildhood and adolescence are periods of rapid bone mass accrual. During this phase, bone mass in females increases from approximately 70 g to 2400 g, and in males from approximately 95 g to 3300 g. This is a critical period for the accumulation of peak bone mass. Promoting bone mass accumulation starting from childhood and adolescence can significantly enhance peak bone mass, delay the onset of osteoporosis, and mitigate its severity. Since BMD serves as a comprehensive indicator of bone mass status, research on BMD in children and adolescents holds significant public health relevance.\u003c/p\u003e \u003cp\u003eSkeletal growth is closely related to physical growth and development. As age increases, height and weight of children and adolescents increase accordingly, along with skeletal growth and an increase in BMD. Numerous studies have demonstrated that BMD increases with age during childhood and adolescence \u003csup\u003e【\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e,\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e,\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e】\u003c/sup\u003e.Consistent with these findings, the present study also observed a clear positive correlation between BMD at various skeletal sites and age, indicating that BMD increases with age.\u003c/p\u003e\n\u003ch3\u003eLimitations\u003c/h3\u003e\n\u003cp\u003eThis study has several limitations. First, it was conducted at a single school, which may limit generalizability. Second, the retrospective design relied on questionnaire results, and incomplete questionnaire led to the exclusion of some cases. Third, dietary data were self-reported by children, which may introduce bias. Despite these limitations, the study provides valuable insights into the correlation between dietary intake and bone density.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eBone mineral density (BMD) in school-aged children increases with age. Boys generally exhibited higher BMD levels than girls. Among children with normal body composition, body mass index (BMI) was positively correlated with BMD, while among overweight and obese children, BMI was negatively correlated with BMD. Increased dietary intake of cereals, tubers, eggs, and fruits was associated with a reduced risk of low BMD. These associations warrant further investigation through experimental studies. The BMD of school-aged children in Yichang City is jointly influenced by age, sex, body composition, and dietary patterns. Maintaining a healthy body weight serves as the foundation for bone health. On this basis, increasing the intake of eggs and fruits can further improve BMD. The negative effects of overweight and obesity on bone metabolism deserve heightened attention.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003cb\u003eEthics Statement\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThis manuscript presents a conceptual and methodological protocol developed within an independent research program. No data involving human participants were collected, generated, or analyzed as part of the present work.\u003c/p\u003e \u003cp\u003eThe proposed protocol is intended to inform future empirical research involving vulnerable pediatric populations. Formal ethical approval will be sought from the appropriate Human Research Ethics Committee (HREC) at the host institution prior to the commencement of any study involving human participants.\u003c/p\u003e \u003cp\u003eThe protocol has been designed in accordance with the precautionary principle. Given the limited capacity for verbal assent in the target population, the absence of a behavioral response is not interpreted as consent. The protocol explicitly integrates physiological and behavioral indicators as markers of potential non-verbal dissent, and any such indicators would lead to immediate termination of the session in future implementations.\u003c/p\u003e \u003cp\u003eGenerative AI tools were used during the preparation of the manuscript to facilitate linguistic revision from French to academic English. This tool was not used to generate scientific content, interpret data, or draw conclusions. All content has been reviewed, verified, and approved by the author.\u003c/p\u003e\n\u003cp\u003eEthics Statement This retrospective analysis of clinical data qualified for an exemption from ethical approval by the Ethics Committee of Tongji Hospital affiliated to Tongji Medical College of HUST. The study adhered to the ethical principles of the Declaration of Helsinki. The publication of this report and any accompanying images has been granted a waiver of written informed consent from the patient. \u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eChinese Nutrition Society (2001) Chinese Dietary Reference Intakes [M]. China Light Industry, Beijing, pp 17\u0026ndash;19\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGe KY, Chang SY (1999) Dietary intake of micronutrients by Chinese residents. Acta Nutrimenta Sinica 21(1):1\u0026ndash;7\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang Y (2012) A study on the relationship between maternal dietary quality, gestational weight gain, and neonatal birth weight (Master's thesis). Anhui Medical University, Anhui, China\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGeneral Administration of Quality Supervision (2014) Inspection and Quarantine of the People's Republic of China, \u0026amp; Standardization Administration of the People's Republic of China. *Comprehensive evaluation of developmental level for children and adolescents*. GB/T 31178\u0026thinsp;\u0026ndash;\u0026thinsp;2014. [Chinese national standard].\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eXiong F, Yang F, Yang SF et al (2014) Relationship between 25-hydroxyvitamin D and bone mineral density in children aged 0\u0026ndash;7 years. *Chinese J Contemp Pediatr 16(9):883\u0026ndash;886\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWang YN (2018) Methodological comparison of growth curve construction and its medical application studies (Master's thesis). Chongqing Medical University, Chongqing, China\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNakavachara P, Pooliam J, Weerakulwattana L et al A normal reference of bone mineral density (BMD) measured by dual energy X-ray absorptiometry in healthy thai childrenand adolescents aged 5\u0026ndash;18 years: a new reference for Southeast Asian Populations[J]. Plos One,2014,9(5):e97218\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Huazhong University of Science and Technology","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-9054593/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9054593/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eOBJECTIVE:\u003c/strong\u003e The aim of this study was to find out the dietary intake of schoolchildren by means of questionnaires and bone densitometry, and to investigate the correlation between dietary intake and bone density.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRESULTS\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study found that BMD among school-age children increased with age. Boys had generally higher BMD than girls. Among children with normal body type, BMI was positively associated with BMD, whereas among overweight and obese children, BMI was negatively associated with BMD. Multivariate regression analysis showed that consuming at least one egg per day (β = 0.011, 95% CI: 0.003–0.019) and at least two servings of fruit per day (β = 0.009, 95% CI: 0.001–0.017) were independent protective factors for BMD. Notably, high intake of dairy products did not show significant benefits in the overweight/obese group (p \u0026gt; 0.05), suggesting that body type may attenuate the beneficial effects of dietary calcium.\u003c/p\u003e","manuscriptTitle":"Analysis of the current status of bone density among primary and secondary school students and its influencing factors","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-17 05:01:14","doi":"10.21203/rs.3.rs-9054593/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"5b791e4c-cb1f-4cce-804e-1163c4674e05","owner":[],"postedDate":"March 17th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":64082260,"name":"Pediatrics"}],"tags":[],"updatedAt":"2026-03-17T05:01:14+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-17 05:01:14","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9054593","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9054593","identity":"rs-9054593","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}